Clinical Cytogenetics Flashcards
Nucleosomes
fundamental packaging unit of DNA
p arm
‘petite,’ short arm
q arm
long arm
Giemsa banding
analysis
cultured cells arrested in metaphase (treated with colchicine)
metacentric
centromere in center
submetacentric
short and long arm
acrocentric
have ‘very tiny short arms’
centromere stats
alphoid DNA repeat unit
telomere stats
beta satellite outer, tandem hexanucleotide repeats (5-TTAGGG-3)
what stage does in cell cycle does DNA replication occur?
S phase
what happens in G2?
cell prepares to undergo mitosis
how many double helix are there beginning of S1?
1
when does a cell have two double helices?
end of S
when does recombination occur
meiosis 1, prophase 1
when does reproduction arrest in female meiosis?
prophase 1
what is a disadvantage to FISH and SKY methods?
need living cells unlike Array CGH
when can nondisjunction occur
in meiosis 1 or 2
what karyotype is associated with turner
45,X
what karyotype is associated with klinefelter
47,XXY
what karyotype is associated with the most common chrom. abnormality?
47,XYY
what is the normal karyotype
46,XY
down syndrome karyotype
47,XX+21 47,XY+21
patau syndrome karyotype
47,XX+13 47,XY+13
edwards syndrome karyotype
47,XX+18 47,XY+18
robertsonian translocation
acrosonian, fusion of short arms
reciprocal translocation
exchange of either/or centric and acentric
mosaicism
nondisjunction that occurs during mitosis
